单击按钮时,我尝试从线程向UIThread发送Toast消息。 但是,每次单击按钮时,Toast都不会出现。 我正在使用Handler来做这件事。
这是完整的代码,以防我在某处犯了一个重大错误:
package google.map.activity;
//imports
public class GoogleMapActivity extends MapActivity {
int lat = 0;
int lng = 0;
Location location;
MapController mc;
GeoPoint p;
private MapController mapController;
private MapView mapView;
private LocationManager locationManager;
// ////////////////////////////////////////////////////////////////////////////////////////////////////////
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.googlemapactivity);
mapView = (MapView) findViewById(R.id.mapView);
mapView.setBuiltInZoomControls(false);
mapView.setSatellite(false);
mapController = mapView.getController();
mapController.setZoom(19);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 5,
0, new GeoUpdateHandler());
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 5, 0, new GeoUpdateHandler());
// //////---Switch to
// Start/////////////////////////////////////////////////////////////////////////////
Button switchToMain = (Button) findViewById(R.id.switchtomain);
switchToMain.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(final View view) {
final Intent intent = new Intent();
setResult(RESULT_OK, intent);
finish();
}
});
// ////--Call a
// Cab/////////////////////////////////////////////////////////////////////////////////////
Button getCab = (Button) findViewById(R.id.GetCab); // create the Button
final Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
getCab.setOnClickListener(new View.OnClickListener() {
String bestProvider = locationManager.getBestProvider(criteria,
true);
Location locationTest = locationManager
.getLastKnownLocation(bestProvider); // get
// last
// known
// location fix from
// locationManager
public void getAddress() {
String msg = null;
Looper.prepare();
if (locationTest == null) {
bestProvider = LocationManager.NETWORK_PROVIDER;
}
Location location = locationManager
.getLastKnownLocation(bestProvider);
Geocoder geocoder = new Geocoder(getBaseContext(), Locale
.getDefault());// create
// new
// GeoCoder
String result = null; // initialize result
try { // try to get Address list from location of bestProvider
List<Address> list = geocoder.getFromLocation(
location.getLatitude(), location.getLongitude(), 1);
if (list != null && list.size() > 0) {
Address address = list.get(0);
// sending back first address line and locality
result = address.getAddressLine(0) + ", "
+ address.getLocality();// set result
// to
// Streetname+Nr.
// and City
}
} catch (IOException e) {
msg = String.format("IOException!!");
} finally {
if (result != null) {
msg = String.format(result);
// Looper.loop();
} else
msg = String.format("Keine Position");
}
Message myMessage = new Message();
Bundle resBundle = new Bundle();
resBundle.putString("status", msg);
myMessage.obj = resBundle;
handler.sendMessage(myMessage);
}
@Override
public void onClick(View v) {
new Thread(new Runnable() {
public void run() {
// Looper.myLooper();
// Looper.prepare();
getAddress(); // get the Address
Location locationTest = locationManager
.getLastKnownLocation(bestProvider);
if (locationTest == null) {
bestProvider = LocationManager.NETWORK_PROVIDER;
}
Location location2 = locationManager
.getLastKnownLocation(bestProvider);
int lat = (int) (location2.getLatitude() * 1E6); // get
// position
// for GeoPoint
int lng = (int) (location2.getLongitude() * 1E6);
GeoPoint point = new GeoPoint(lat, lng); // create
// GeoPoint
// for
// mapController
mapController.animateTo(point);
}
}).start();
// toast.show();
}
});
}
public Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
Toast.makeText(getApplicationContext(), msg.toString(),
Toast.LENGTH_LONG);
}
};
public class GeoUpdateHandler implements LocationListener {
@Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude() * 1E6);
int lng = (int) (location.getLongitude() * 1E6);
GeoPoint point = new GeoPoint(lat, lng);
mapController.animateTo(point); // mapController.setCenter(point);
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
}
提前谢谢!
编辑:使用此解决方法:
Handler toastHandler = new Handler();
Runnable toastRunnable = new Runnable() {public void run() {Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();}};
在UIThread和this:
toastHandler.post(toastRunnable);
在后台线程中。
答案 0 :(得分:4)
试试这个:
runOnUiThread(new Runnable()
{
public void run()
{
// Here you can make a Toast
}
});
答案 1 :(得分:3)
您的Toast需要在UI线程中完成。以下是如何做到这一点:
注意:ClassName.this
是必需的,因为this
本身会引用您的匿名Runnable
类。
runOnUiThread(new Runnable() {
@Override
public void run()
{
Toast.makeText(ClassName.this, R.string.something, Toast.LENGTH_LONG).show();
}
});